Control of access to a secondary system

ABSTRACT

A method and system for controlling access of a user to a secondary system. A primary system sends a random string to a user system that is connected to the secondary system. The user is logged on the user system. The primary system receives from the user system first authentication information including an encryption of the random string by a private key of the user. The primary system generates a user-specific key consisting of the encryption of the random string.

This application is a continuation application claiming priority to Ser.No. 13/472,664, filed May 16, 2012, which is a continuation of Ser. No.11/546,665, filed Oct. 12, 2006, U.S. Pat. No. 8,230,487, issued Jul.24, 2012.

FIELD OF THE INVENTION

The invention relates to a method and a data processing system forcontrolling the access of a user to a secondary system.

BACKGROUND OF THE INVENTION

A typical scenario in modern day computing is a user who is logged in toa primary system from a user system and who wants to log in to asecondary system from the primary system. Unfortunately, current methodsin the related art for controlling access of a user to a secondarysystem have security risks, and administrators (e.g., systemadministrators) may be subject to suspicion when security-relatedincidents occur.

Thus, there is therefore the need for an improved method and system forcontrolling the access of a user to a secondary system, wherein theimproved method and system alleviates and/or mitigates theaforementioned difficulties associated with current methods in therelated art for controlling access of a user to a secondary system.

SUMMARY OF THE INVENTION

The present invention provides a method for controlling access of a userto a secondary system, said user being logged on a user system, aprimary system connecting the user system to the secondary system, saidmethod comprising:

receiving first authentication information from the user system;

determining that the first authentication information conforms toprotected primary authentication data comprised by the primary system,followed by providing access of the user to the primary system;

after providing access of the user to the primary system, generating auser-specific key from the first authentication information;

deriving second authentication information from protected secondaryauthentication data comprised by the primary system, said deriving thesecond authentication information comprising using the user-specific keyin conjunction with the protected secondary authentication data; and

providing the second authentication information to the secondary systemto enable access of the user to the secondary system, wherein saidreceiving first authentication information, said determining andproviding access, said deriving the second authentication information,and said providing the second authentication information to thesecondary system are performed by the primary system.

The present invention provides a computer program product comprisingcomputer executable instructions for performing a method for controllingaccess of a user to a secondary system, said user being logged on a usersystem, a primary system connecting the user system to the secondarysystem, said method comprising:

receiving first authentication information from the user system;

determining that the first authentication information conforms toprotected primary authentication data comprised by the primary system,followed by providing access of the user to the primary system;

after providing access of the user to the primary system, generating auser-specific key from the first authentication information;

deriving second authentication information from protected secondaryauthentication data comprised by the primary system, said deriving thesecond authentication information comprising using the user-specific keyin conjunction with the protected secondary authentication data; and

providing the second authentication information to the secondary systemto enable access of the user to the secondary system, wherein saidreceiving first authentication information, said determining andproviding access, said deriving the second authentication information,and said providing the second authentication information to thesecondary system are performed by the primary system.

The present invention provides a primary system comprising a processorand a computer program product, said computer program product comprisingcomputer executable instructions that when executed by the processorperform a method for controlling access of a user to a secondary systemwhen the user is logged on a user system subject to the primary systemconnecting the user system to the secondary system, said methodcomprising:

receiving first authentication information from the user system;

determining that the first authentication information conforms toprotected primary authentication data comprised by the primary system,followed by providing access of the user to the primary system;

after providing access of the user to the primary system, generating auser-specific key from the first authentication information;

deriving second authentication information from protected secondaryauthentication data comprised by the primary system, said deriving thesecond authentication information comprising using the user-specific keyin conjunction with the protected secondary authentication data; and

providing the second authentication information to the secondary systemto enable access of the user to the secondary system.

The present invention provides an improved method and system forcontrolling the access of a user to a secondary system, wherein theimproved method and system alleviates and/or mitigates difficultiesassociated with current methods in the related art for controllingaccess of a user to a secondary system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a computer network, in accordance withembodiments of the present invention.

FIG. 2 is a flow diagram for performing a method, in accordance with theinvention, in accordance with embodiments of the present invention.

FIG. 3 is a block diagram of a computer network of an access managementsystem, in accordance with embodiments of the present invention.

FIG. 4 is a table illustrating use of the access management system ofFIG. 3, in accordance with embodiments of the present invention.

FIG. 5 is a flow chart describing generation of a user-specific key, inaccordance with embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with an embodiment of the present invention, there isprovided a method for controlling the access of a user to a secondarysystem, wherein the user is logged on a user system, wherein thesecondary system and the user system are interconnected by a primarysystem, wherein the primary system comprises a credential store, whereinthe credential store comprises protected primary authentication data andprotected secondary authentication data and wherein the method comprisesthe step of receiving first authentication information from the user forthe primary system and the step of comparing the first authenticationinformation with the protected primary authentication data so thataccess is provided for the user to the primary system if the firstauthentication information conforms to the protected primaryauthentication data. The method further comprises the step of generatinga user-specific key from the first authentication information and thestep of deriving a second authentication information by decryption ofthe protected secondary authentication data by use of the user-specifickey. The second authentication information is provided to the secondarysystem to enable access by the user to the secondary system.

There is therefore no single key which is used to encrypt theauthentication information of all users. Instead, there is auser-specific key which is generated during a session by use of thefirst authentication information. The user-specific key is used todecrypt the second authentication data and thereby deriving a secondauthentication information. Since there is no general key for decryptingthe authentication data of all users, the attractiveness of breakingsuch an general key has vanished. Neither the system administrator northe database administrator nor any other administrator of a computersystem that comprises the credential store has access to such a generalkey since such a general key does not exist. As a consequence, theprotection of the various administrators against false suspicion israised enormously. Even having access to the secondary session data, thesystem administrator can only compromise user-specific keys that arecurrently in use. This narrows down the cases in which false suspicioncan arise, in particular when combined with other typical methods (e.g.tracking administrative access). In particular, the benefits from havingno single key for the credential store becomes apparent. This way alsoauditability is supported. Since the credential database containsdifferently encrypted data, attacking is much more difficult. Also knownplain text attacks are ruled out.

In accordance with an embodiment of the present invention, theuser-specific key is stored during a session of the user on the primarysystem and the secondary authentication information is only generatedand provided to the secondary system during the session in which theuser requests access to the secondary system. Thus the secondauthentication information is only available during a session if theuser uses the secondary system. As a consequence, the time when a systemadministrator has access to the second authentication information is cutdown to the time when the user is logged on the secondary system. Thisnarrows down the cases in which false suspicion can arise against thesystem administrator.

In accordance with an embodiment of the present invention, the methodcomprises the step of deleting the user-specific key when the user logsoff from the primary system. Any user-specific data which is requiredfor accessing the secondary system is only stored during a session onthe primary system. This lowers the risk of making available thesecondary authentication information to anybody else than the user. Inaddition to the user-specific key, the secondary authenticationinformation is also deleted when the user logs off from the primarysystem.

In accordance with an embodiment of the present invention, the methodcomprises the step of requesting a second secondary authenticationinformation from the user if the stored protected secondaryauthentication data is not valid or not available and the step ofgenerating a second protected secondary authentication data by two wayencryption of the second secondary authentication information by use ofthe user-specific key. The method further comprises the step ofreplacing said invalid or unavailable protected secondary authenticationdata by the second protected secondary authentication data.

In accordance with an embodiment of the present invention, the methodcomprises the steps of receiving a request from the user after the userhas accessed the primary system and in which the user requests a changeof the protected primary authentication data. In response to the requesta second primary authentication information is requested from the user.The second primary authentication information is transformed into asecond protected primary authentication data which replaces theprotected primary authentication data. The method further comprises thestep of generating a second secondary authentication data by two wayencrypting the secondary authentication information by use of the secondprimary authentication information in the step of replacing thesecondary authentication data by the second secondary authenticationdata. Thus the method provides steps for enabling a user to change theprimary authentication information. It is also ensured that thesecondary authentication data reflects the change of the primaryauthentication information. A user is free to change primaryauthentication information. This ensures that the security risks arekept low.

In accordance with an embodiment of the present invention, the firstauthentication information is a user-specific password which is one wayencrypted with a first encryption method and then compared with theprotected primary authentication data. Moreover the user-specific key isgenerated by one way encryption of the password with a second encryptionmethod.

In accordance with an embodiment of the present invention, the firstencryption method and the second encryption method are provided by twodifferent hash functions.

In accordance with an embodiment of the present invention, the firstauthentication information is a user-specific private key which isapplied on user-specific data. The result of the application of theuser-specific private key on the user-specific data is compared with theprimary authentication data by use of a public key. The public key isstored in the credential store and the user-specific key is generated byapplying the user-specific private key to the user-specific data.

In another aspect the invention relates to a computer program productcomprising computer executable instructions for performing a method inaccordance with the present invention.

In another aspect, the present invention relates to a data processingsystem for controlling the access of a user to a secondary system for auser. The user is logged on a user system and the secondary system andthe user system are interconnected by a primary system. The primarysystem comprises a credential store and the credential store comprisesprotected primary authentication data and protected secondaryauthentication data. The data processing system comprises means forreceiving a first authentication information from the user for theprimary system and means for comparing the first authenticationinformation with the protected primary authentication data. The dataprocessing system further comprises means for generating a user-specifickey from the first authentication information and means for generating asecond authentication information by decryption of the protectedsecondary authentication data by use of the user-specific key andfurther means for providing the second authentication information to thesecondary system.

FIG. 1 shows a block diagram of a computer network 100, in accordancewith embodiments of the present invention. The network 100 comprises auser system 102, a primary system 104, and a secondary system 108. Theuser system 102 is connected to the primary system 104 via the networkconnection 122, and the primary system 104 is connected to the secondarysystem 108 via the network connection 124. The user system 102 comprisesa volatile memory device 110, an input device 112, a screen 114, amicroprocessor 116, and a non-volatile memory device 118.

The primary system 104 comprises a credential store 106, a volatilememory device 130, a non-volatile memory device 132, and amicroprocessor 134. The volatile memory device 130 comprises auser-specific key 138 and secondary authentication information 140. Thecredential store 106 comprises primary authentication data 126 andsecondary authentication data 128. The microprocessor 134 comprises acomputer program product 136 and a first application 142.

The secondary system 108 comprises a non-volatile memory device 144, avolatile memory device 146 and a microprocessor 148.

A user is logged on the user system and starts a session by providing afirst authentication information 120 to the primary system 104. Thefirst authentication information 120 is derived from user-specificauthentication data such as a password or private key of the user. Theuser-specific authentication data (e.g., password or private key) may beprovided by the user by use of the input device 112 to the user system102. In one embodiment, the first authentication information 120 isneither stored on the volatile memory device 110 nor on the non-volatilememory device 118. The first authentication information 120 is generatedfrom the user-specific authentication data via processing theuser-specific authentication data by the microprocessor 116. The firstauthentication information 120 is provided by the network connection 122to the primary system 104. The network connection 122 may be a protectedcommunication channel. For protection of the communication channel,standard technologies such as SSL (Secure Socket Layer) or VPN (VirtualPrivate Network) can be used.

The first authentication information 120 is received by the primarysystem 104. The microprocessor 134 executes the computer program product136 which comprises instructions for performing the method in accordancewith the present invention. The credential store 106 comprises protectedprimary authentication data 126. The microprocessor 134 compares thefirst authentication information 120 with the primary authenticationdata 126 in the following ways.

If the first authentication information 120 is a password, then thepassword is sent to the primary system as the first authenticationinformation 120 and thereafter is one way encrypted by the primarysystem 104 with a first encryption method and the one way encryptedpassword is the processed first authentication information 120 that iscompared with the protected primary authentication data 126. If thefirst authentication information 120 is a password, then the firstauthentication data 120 is considered to conform to the protectedprimary authentication data 126 if the one way encrypted password isequal to the protected primary authentication data 126.

One way encryption is characterized by the fact that encrypted datacannot be decrypted; the encrypted data is used only for comparison withother encrypted data. In contrast, two way encryption is characterizedby the fact that data can be encrypted and decrypted at some later pointin time.

If the first authentication information 120 is derived from a privatekey applied on a random string such that the random string is derivedfrom user-specific data pertaining to the user, then the random stringis sent by the primary system 104 to the user system 102. Applying theprivate key on the user-specific data (e.g., random string) means usingthe private key to encrypt the user-specific data (e.g., random string).The private key is applied to the random string by the user system 102and then sent back to the primary system 104 as the processed firstauthentication data 120. The processed first authentication information120, which is the private key applied on the random string, is comparedby the computer program product 136 with the primary authentication data126 by use of a public key that is associated with the private key. Thepublic key is used to decrypt the first authentication data 120.Comparing the first authentication data 120 with the primaryauthentication data 126 by use of a public key means that the dataresulting from decrypting the first authentication data 120 through useof the public key is compared with the primary authentication data 126.Thus if the first authentication information 120 is a private keyapplied on user-specific data (e.g., random string), then the firstauthentication data 120 is considered to conform to the protectedauthentication data 126 if the data resulting from decrypting the firstauthentication data 120 through use of the public key is equal to theprotected authentication data 126.

If the first authentication information 120 conforms to the protectedauthentication data 126, then the user can access the primary system.The user can then use a first application 142 which is executed by themicroprocessor 134 on the primary system 104. The first application 142is for example a portal. If the first authentication information 120does not conform to the protected authentication data 126, then the useris rejected.

From the first authentication information 120, a user-specific key 138is generated by use of the computer program product 136 and stored onthe volatile memory device 130. If the first authentication information120 is a password, then the user-specific key 138 is generated by oneway encryption of the password with the second encryption method whichdiffers from the first encryption method. If the first authenticationinformation 120 is derived from a private key, then the private key isapplied at the user system 102 to a random string derived from userdependent data. The random string derived from user dependent data isprovided to the user system 102 by the primary system 104. The valuecomputed from applying the private key to the random string is sent bythe user system 102 to the primary system 104 becomes the user-specifickey 138.

The user might want to access the secondary system 108 from the primarysystem 104. Such a situation arises for example when the firstapplication 142 comprises a portal through which applications on thesecondary system 108 are accessed. For accessing the secondary system108, a second authentication information 140 is derived and stored onthe volatile memory device 130 by decryption of the protected secondaryauthentication data 128 by use of the user-specific key applied to thesecondary authentication data 128, or alternatively by two wayencryption of the protected secondary authentication data by use of theuser-specific key applied to the secondary authentication data 128 asdiscussed infra in conjunction with the illustrated example of FIG. 4.The secondary authentication information 140 is provided via the networkconnection 124, which is also a protected communication channel, to thesecondary system 108, so that the user is logged on the secondarysystem. The user can now use the second application 150 executed by themicroprocessor 148 of the secondary system 108 via the primary system104 from the user system 102.

The secondary authentication information 140 can be generated asdescribed above when the user requests access to the secondary system108. Alternatively the secondary authentication information 140 can begenerated when the user logs onto the primary system 104 and stored onthe volatile memory device 130 or alternatively on the non-volatilememory device 132. However, when the user ends his session, thesecondary authentication information 140 and the user-specific key 138are deleted from the volatile memory device 130 or from the non-volatilememory device 132.

The primary authentication data 126 and the secondary authenticationdata 128 are established through the following process. Initially thesystem administrator sets the primary authentication data 126. If theuser accesses the secondary system 108 via the primary system 104 and nosecondary authentication data 128 is stored (or is not valid), thecomputer program product 136 prompts the user in order to demandsecondary authentication information, from which the secondaryauthentication data 128 is generated by encrypting the secondauthentication information provided by the user. Alternatively, thesecond authentication data 128 can be provided by the systemadministrator when setting the primary authentication data 126.

The primary authentication data 126 may be changed by the followingprocedure: if the user is logged on the primary system and requests achange of the primary authentication data 126. The user is prompted fora new first authentication information. Since at this point the primarysystem 104 has both the current first authentication information 120 andthe new first authentication information, the computer program product136 decrypts all the stored secondary information data 128 using thefirst authentication information 120 and encrypts it afterwards with thenew first authentication information which is then replacing the secondinformation data in the credential store 106.

The primary authentication data 126 may be changed by the followingalternative procedure. A second primary authentication information isrequested and received from the user. The obtained second primaryauthentication information is transformed into a second protectedprimary authentication data which replaces the protected primaryauthentication data. A second secondary authentication data is generatedby two-way encrypting the secondary authentication information 128 byuse of the obtained second primary authentication information. Thegenerated second secondary authentication data replaces the secondaryauthentication data 128.

When authentication of the user to the secondary system 108 is notsuccessful, the user is notified and prompted for updating the secondaryauthentication data 128. If the user provides secondary authenticationinformation 140, then the secondary authentication information 140 isencrypted from which the secondary authentication data 128 is generated.

If the stored protected secondary authentication data 128 is not validor not available, the following procedure may be used. Second secondaryauthentication information is requested and received from the user. Asecond protected secondary authentication data is generated by two-wayencryption of the obtained second secondary authentication informationby use of the user-specific key 138. The invalid or unavailableprotected secondary authentication data 128 is replaced by the generatedsecond protected secondary authentication data.

FIG. 2 depicts a flow diagram for performing a method, in accordancewith embodiments of the present invention. The method may be performedby the computer program product 136 in the primary system 104 of FIG. 1.In step 200, a first authentication information 120 is received from auser requesting access to the primary system 106. In step 202, thegenerated function of the first authentication information 120 ischecked for conformance against the primary authentication data 126which is stored in the credential store 106 of the primary system 104.If step 202 determines that there is a difference between the primaryauthentication data 126 and the generated function of the firstauthentication information 120, then the user is rejected in step 204.If step 202 determines that there is no difference between the primaryauthentication data 126 and the first authentication information 120,then the method proceeds with step 206, wherein a user-specific key 138is generated from the first authentication information 120, as describedin FIG. 5.

FIG. 5 is a flow chart describing generation of a user-specific key, inaccordance with embodiments of the present invention. Step 501determines if the first authentication information 120 is a password oris derived from a private key.

If step 501 determines that the first authentication information 120 isa password, then the primary system 104 generates the user-specific keyas a one-way hash of the password via the second encryption methoddescribed supra. If step 501 determines that the first authenticationinformation 120 is derived from a private key, then: in step 503 theprimary system 104 sends a random string to the user system 102; in step504 the user system 102 applies the private key to the random string;and in step 505 the user system 102 sends to the primary system 104 theprivate key applied to the random string as the user-specific key. Notethe user specific key is “user-specific” because the user specific keyis a function of user data that is specific to the user, namely the userdata of the user's password or the user's private key.

In step 208 of FIG. 2, a secondary authentication information 140 isgenerated by decryption of the secondary authentication data 128 by useof the user-specific key 138. The secondary authentication information140 is provided to the secondary system 108 in step 210 so that in step212 the user is logged on the secondary system 108.

FIG. 3 shows a block diagram of a computer network 300 of an accessmanagement system, in accordance with embodiments of the presentinvention. The computer network 300 comprises a user system 302, aprimary system 304, and three secondary systems: secondary system 306,secondary system 308, and secondary system 310.

FIG. 4 is a table 312 illustrating use of the access management systemof FIG. 3, in accordance with embodiments of the present invention. Thetable 312 comprises a list of users which can access the secondarysystems 306, 308, and 310 from the primary system 304 along withinformation about how the primary system 304 and the secondary system306, 308, and 310 are accessed. The primary system 304 represents theprimary system 104 of FIG. 1. The secondary systems 306, 308, and 310each represent the secondary system 108 of FIG. 1.

In line 314, the user name is Frank A. Frank A uses the password“my99sec” to authenticate himself against the primary system 304. Asshown in the second column of line 314, the password “my99sec”, which isthe first authentication information 120, is one way encrypted by thefirst hash function H_a and then compared with the primaryauthentication data 126 stored in the credential store 106. Frank A canaccess the primary system 304 if the hash function H_a applied to thepassword “my99sec” provided by Frank A is equal to the primaryauthentication data 126. In order to access the secondary systems 306,308 or 310, a user-specific key 138 is generated by use of the password“my99sec”. This is done as shown in the third column of line 314 by oneway encrypting the password “my99sec” with a second hash function H b.The user-specific key 138 is then H b(my99sec). The secondaryauthentication information 140 of each secondary system, 306, 308, or310, is then generated by two way encryption of the secondaryauthentication data 128 of each secondary system 306, 310, or 310,respectively. The two way encryption function is E(H_b(my99sec)) inwhich the functional value of H_b(my99sec) is used as an argument (i.e.as key). Thus by two way encryption of the secondary authentication data128 of the secondary system 306, the secondary authenticationinformation 140 “mypass” is generated. By two way encryption of thesecondary authentication data 128 of the secondary system 308, thesecondary authentication information 140 “0607” is generated. By two wayencryption of the secondary authentication data of the secondary system310, the secondary authentication information 140 “frank99” isgenerated.

In line 316, the user name is Ann B. Ann B uses the password “ysxjik” toauthenticate herself against the primary system 304. As shown in thesecond column of line 316, the password “ysxjik”, which is the firstauthentication information 120, is one way encrypted by the first hashfunction H_a and then compared with the primary authentication data 126stored in the credential store 106. Ann B can access the primary system304 if the hash function H_a applied to the password “ysxjik” providedby Anne B is equal to the primary authentication data 126. In order toaccess on of the secondary systems 306, 308 or 310, a user-specific key138 is generated by use of the password “ysxjik”. This is done as shownin the third column of line 314 by one way encrypting the password“ysxjik” with a second hash function H_b. The user-specific key 138 isthen H_b(ysxjik). The secondary authentication information 140 of eachsecondary system, 306, 308, or 310, is then generated by two wayencryption of the secondary authentication data 128 of each secondarysystem 306, 310, or 310, respectively. The two way encryption functionis E(H_b(ysxjik)) in which the functional value of H_b(ysxjik) is usedas an argument (i.e. as key). Thus by two way encryption of thesecondary authentication data 128 of the secondary system 306, thesecondary authentication information 140 “asdl” is generated. By two wayencryption of the secondary authentication data 128 of the secondarysystem 308, the secondary authentication information 140 “m&m” isgenerated. By two way encryption of the secondary authentication data128 of the secondary system 310, the secondary authenticationinformation 140 “summer05” is generated.

In line 318, the user name is Nicole C. Nicole C uses the password“nic8ole” to authenticate herself against the primary system 304. Asshown in the second column of line 318, the password “nic8ole”, which isthe first authentication information 120, is one way encrypted by thefirst hash function H_a and then compared with the primaryauthentication data 126 stored in the credential store 106. Nicole C canaccess the primary system 304 if the hash function H_a applied to thepassword “nic8ole” provided by Nicole C is equal to the primaryauthentication data 126. In order to access on of the secondary systems306, 308 or 310, a user-specific key 138 is generated by use of thepassword “nic8ole”. This is done as shown in the third column of line314 by one way encrypting the password “nic8ole” with a second hashfunction H_b. The user-specific key 138 is then H_b(nic8ole). Thesecondary authentication information 140 of each secondary system, 306,308, or 310, is then generated by two way encryption of the secondaryauthentication data 128 of each secondary system 306, 310, or 310,respectively. The two way encryption function is E(H_b(nic8ole)) inwhich the functional value of H_b(nic8ole) is used as an argument (i.e.as key). Thus by two way encryption of the secondary authentication data128 of the secondary system 306, the secondary authenticationinformation 140 “n1ccy” is generated. By two way encryption of thesecondary authentication data 128 of the secondary system 308, thesecondary authentication information 140 “mace04” is generated. By twoway encryption of the secondary authentication data 128 of the secondarysystem 310, the secondary authentication information 140 “imhoidbi” isgenerated.

While embodiments of the present invention have been described hereinfor purposes of illustration, many modifications and changes will becomeapparent to those skilled in the art. Accordingly, the appended claimsare intended to encompass all such modifications and changes as fallwithin the true spirit and scope of this invention.

What is claimed is:
 1. A method for controlling access of a user to asecondary system, said method comprising: a processor of a primarysystem sending a random string to a user system, said processorconnecting the user system to the secondary system, said user beinglogged on the user system; and after said sending the random string tothe user system, said processor receiving from the user system firstauthentication information comprising an encryption of the random stringby a private key of a public/private key pair of the user.
 2. The methodof claim 1, wherein the method further comprises: after said receivingthe first authentication information, said processor generating auser-specific key consisting of the encryption of the random string inthe first authentication information; and said processor storing theuser-specific key in the primary system.
 3. The method of claim 2,wherein the method further comprises: said processor generating secondauthentication information from protected secondary authentication datastored in the primary system, said generating the second authenticationinformation comprising applying the user-specific key to the protectedsecondary authentication data to generate the second authenticationinformation; and said processor providing the second authenticationinformation to the secondary system to enable access of the user to thesecondary system.
 4. The method of claim 3, wherein the method furthercomprises: after said receiving the first authentication information andbefore said generating the user-specific key, said processor determiningthat a decryption or an encryption of the first authenticationinformation is equal to protected primary authentication data stored inthe primary system, followed by said processor providing access of theuser to the primary system.
 5. The method of claim 4, wherein the methodfurther comprises: said processor receiving a request from the user tochange the protected primary authentication data; said processorrequesting second primary authentication information from the user; saidprocessor transforming the second primary authentication informationinto second protected primary authentication data; said processorreplacing the protected primary authentication data by the secondprotected primary authentication data; said processor generating secondsecondary authentication data by two-way encrypting the secondauthentication information by use of the second primary authenticationinformation; and said processor replacing the second authentication databy the second secondary authentication data.
 6. The method of claim 3,wherein the method further comprises: receiving second secondaryauthentication information from the user; generating second protectedsecondary authentication data by two-way encryption of the secondsecondary authentication information by use of the user-specific key;and replacing the protected secondary authentication data by the secondprotected secondary authentication data.
 7. The method of claim 3,wherein said generating the second authentication information comprisesperforming a decryption of the protected secondary authentication databy use of the user-specific key applied to the secondary authenticationdata.
 8. The method of claim 3, wherein said generating the secondauthentication information comprises performing a two way encryption ofthe protected secondary authentication data by use of the user-specifickey applied to the secondary authentication data.
 9. The method of claim3, wherein the primary system comprises an application, said applicationcomprising a portal through which the secondary system may be accessedfrom the user system after access of the user to the secondary systemhas been enabled via said providing the second authenticationinformation to the secondary system.
 10. A computer program productcomprising a computer readable storage device storing computerexecutable instructions that when executed by a processor of a primarysystem perform a method for controlling access of a user to a secondarysystem, said method comprising: said processor sending a random stringto a user system, said processor connecting the user system to thesecondary system, said user being logged on the user system; and aftersaid sending the random string to the user system, said processorreceiving from the user system first authentication informationcomprising an encryption of the random string by a private key of apublic/private key pair of the user.
 11. The computer program product ofclaim 10, wherein the method further comprises: after said receiving thefirst authentication information, said processor generating auser-specific key consisting of the encryption of the random string inthe first authentication information; and said processor storing theuser-specific key in the primary system.
 12. The computer programproduct of claim 11, wherein the method further comprises: saidprocessor generating second authentication information from protectedsecondary authentication data stored in the primary system, saidgenerating the second authentication information comprising applying theuser-specific key to the protected secondary authentication data togenerate the second authentication information; and said processorproviding the second authentication information to the secondary systemto enable access of the user to the secondary system.
 13. The computerprogram product of claim 12, wherein the method further comprises: aftersaid receiving the first authentication information and before saidgenerating the user-specific key, said processor determining that adecryption or an encryption of the first authentication information isequal to protected primary authentication data stored in the primarysystem, followed by said processor providing access of the user to theprimary system.
 14. The computer program product of claim 13, whereinthe method further comprises: said processor receiving a request fromthe user to change the protected primary authentication data; saidprocessor requesting second primary authentication information from theuser; said processor transforming the second primary authenticationinformation into second protected primary authentication data; saidprocessor replacing the protected primary authentication data by thesecond protected primary authentication data; said processor generatingsecond secondary authentication data by two-way encrypting the secondauthentication information by use of the second primary authenticationinformation; and said processor replacing the second authentication databy the second secondary authentication data.
 15. The computer programproduct of claim 12, wherein the method further comprises: receivingsecond secondary authentication information from the user; generatingsecond protected secondary authentication data by two-way encryption ofthe second secondary authentication information by use of theuser-specific key; and replacing the protected secondary authenticationdata by the second protected secondary authentication data.
 16. Aprimary system comprising a processor and a computer program product,said computer program product comprising computer executableinstructions that when executed by the processor perform a method forcontrolling access of a user to a secondary system, said methodcomprising: said processor sending a random string to a user system,said processor connecting the user system to the secondary system, saiduser being logged on the user system; and after said sending the randomstring to the user system, said processor receiving from the user systemfirst authentication information comprising an encryption of the randomstring by a private key of a public/private key pair of the user. 17.The primary system of claim 16, wherein the method further comprises:after said receiving the first authentication information, saidprocessor generating a user-specific key consisting of the encryption ofthe random string in the first authentication information; and saidprocessor storing the user-specific key in the primary system.
 18. Theprimary system of claim 17, wherein the method further comprises: saidprocessor generating second authentication information from protectedsecondary authentication data stored in the primary system, saidgenerating the second authentication information comprising applying theuser-specific key to the protected secondary authentication data togenerate the second authentication information; and said processorproviding the second authentication information to the secondary systemto enable access of the user to the secondary system.
 19. The primarysystem of claim 18, wherein the method further comprises: after saidreceiving the first authentication information and before saidgenerating the user-specific key, said processor determining that adecryption or an encryption of the first authentication information isequal to protected primary authentication data stored in the primarysystem, followed by said processor providing access of the user to theprimary system.
 20. The primary system of claim 19, wherein the methodfurther comprises: said processor receiving a request from the user tochange the protected primary authentication data; said processorrequesting second primary authentication information from the user; saidprocessor transforming the second primary authentication informationinto second protected primary authentication data; said processorreplacing the protected primary authentication data by the secondprotected primary authentication data; said processor generating secondsecondary authentication data by two-way encrypting the secondauthentication information by use of the second primary authenticationinformation; and said processor replacing the second authentication databy the second secondary authentication data.